Skylight structure

ABSTRACT

A skylight structure is formed with condensate channels at the upper portions of the purlins and rafters adjacent glazing panels supported by them. Preferably, the condensate channels and the means for interconnecting the purlin and rafters are concealed. The preferred structural members used as rafters and purlins have hollow closed tubular bodies.

[451 Oct. 29, 1974 SKYLIGHT STRUCTURE [75] lnventors: Hans F. Schultz,Arlington Heights; Carl Radtke, Chicago, both of 111.

[73] Assignee: Roper Corporation, Kankakee, Ill.

[22] Filed: June 22, 1972 [21] Appl. No.: 265,164

[52] US. Cl 52/200, 52/208, 52/209, 52/463, 52/476 [51] Int. Cl E04j13/03 [58] Field of Search 52/200, 208, 209, 210, 52/235, 488, 475, 476,731, 198, 199, 463

[56] References Cited UNITED STATES PATENTS 1,538,817 5/1925 James52/200 1,656,044 l/ 1928 Cibulas 52/200 X 2,885,040 5/1959 Grossman52/208 X 2,901,785 9/1959 l-lrachliffe et al 52/495 X 3,062,339 11/1962Geyser 52/235 X 3,221,453 12/1965 Lietaert 52/209 3,436,887 4/1969Grossman 52/235 3,550,335 12/1970 Huffman 52/200 3,734,550 5/1973 Vance52/235 X OTHER PUBLICATIONS Skylights & Ventilators; Fisher Skylights,lnc.;

Sweets Catalog 1972, Vol. 4, pp. 1-ll, copyright 1971 Natural LightThrough Design-Oriented Glazed Structures; lBG; Sweets Catalog 1972,Vol. 4, pp. l1 1, copyright 1971 Dimensions Unlimited 1972; Super SkyProducts, Inc; Sweets Catalog 1972, Vol. 4, pp. 18-25, copyright 1971Primary Examiner-John E. Murtagh Assistant Examiner-Leslie A. BrownAttorney, Agent, or Firm-Fitch, Even, Tabin & Luedeka ABSTRACT Askylight structure is formed with condensate channels at the upperportions of the purlins and rafters adjacent glazing panels supported bythem. Preferably, the condensate channels and the means fininterconnecting the purlin and rafters are concealed. The preferredstructural members used as rafters and purlins have hollow closedtubular bodies.

6 Claims, 11 Drawing Figures PATENIEDBBIZS I974 WU 10F 5 3,844,087

FIG- 2 (PRIOR ART) (PRIOR ART) 60/ PMENIEMUZSIN v sum 2m: 5 3,844,087

F I G. 4

PATENIEBBWQ m4 Y v 1 SKYLIGHT STRUCTURE This invention relates to askylight structure having purlin and rafter structural members whichsupport glazing panels of uninsulated glass, plastic acrylic or thelike.

Transparent or translucent domes or skylight structures of various kindsare now used in shopping centers, buildings,,libraries, swimming poolstructures and the like. Such structures cover substantially largesurface areas with the rafters and purlins joined to form a grid orskeleton framework for supporting marginal edges of the glazing panels.Preferably, such structures are constructed of lightweight metal purlinsand rafters joined into a rigid and strong skeleton to stand loadsapplied to wide surface areas of the glazing panels. Additionally, asdisclosed in Schultz et al. US. Pat. No. 3,488,899, the external sidesof the outside glazing panels in a skylight structure may be cooled by acold outside atmosphere with the result that the interior surfaces ofthe panels may be cooled to a temperature sufficiently lower than thetemperature of the air in the building that water vapor carried by theinside air condenses on the interior surfaces of the glazing panelsand/or framework. This internal condensate is collected along thepurlins and rafters of the structure in condensate channels or guttersand directed to discharge at a weep hole, an outside gutter or a sewer.

Also, some moisture on the exterior of the glazing panels may leak orbypass a glazing seal or bypass along a fastener and this bypassmoisture is collected in moisture bypass channels which discharge intothe gutter or weep hole.

The provisions of condensate channels and bypass moisture channels onpurlins and rafters has heretofore been generally at the expense of theneatness and an uncluttered look for the purlins and rafters. Also,where condensate is delivered from the purlin moisture collectingchannels to rafter moisture lcarrying channels, the interconnectionbetween purlin and rafters is complicated by the necessity to providethe condensate flow paths while maintaining adequate mechanicalinterconnections. As a result, the mechanical interconnections oftenwere made with exposed connectors and fasteners which detracted from theaesthetics of the structure. Moreover, the bypass moisture channels andcondensate channels were at different levels in the purlins; andsometimes a downward flow of by pass moisture along the rafter caused aback flow of moisture into the lower condensate channelof the purlin.Such a back flow condition is to be avoided.

Accordingly. an object of the present invention is to provide animproved skylight construction having a clean uncluttered look and anefficient moisture removal system.

These and other objects and advantages of the present invention willbecome'apparent from the following detailed description taken inconnection with the accompanying drawings in which:

FIG. I is a diagrammatic perspective view of a skylight structure inwhich the present invention may be embodied;

FIG. 2 is an enlarged, fragmentary, sectional and perspective view ofprior art purlins and rafters supporting glazing panels and having amoisture removal system;

FIG. 3 is another perspective view of the prior art structure shown inFIG. 2;

FIG. 4 is an enlarged, fragmentary, sectional and perspective viewillustrating purlins and rafters arranged in a skylight structure andembodying the present invention;

FIG. 5 is a cross-sectional view taken substantially along the line 5-5of FIG. 4;

FIG. 6 is a diagrammatic exploded view of the purlins and rafter of FIG.4 showing the manner of interconnection therebetween;

FIG. 7 is a sectional view taken substantially along the line 7-7 ofFIG. 6 but with the purlins connected to the rafter;

FIG. 8 is a fragmentary perspective view illustrating another embodimentof the invention for a double glazed skylight construction;

FIG. 9 is another fragmentary, partially exploded, perspective view ofthe structure of FIG. 8;

FIG. 10 is a fragmentary cross-sectional view of the structure of FIG. 8showing purlin and rafter interconnections; and

FIG. 11 is a cross-sectional view taken substantially along the line11-11 in FIG. 10, but with the rafter incliried.

As shown in the drawings for purposes of illustration, the invention isembodied, very generally, in a skylight structure 11 which may be usedin overhead domes in various kinds of buildings in which a roof or aportion of a roof is formed with glazing panels 12 usually oftransparent, tinted or translucent glass or of a plastic such as anacrylic plastic. The glazing panels 12 are supported along marginaledges 15 thereof in a framework 14 of structural members comprisinghorizontally extending purlins 16 and vertically extending rafters 17.

In prior art skylight structures such as those illustrated in FIGS. 2and 3, the framework 14a is cluttered in its appearance by the exposedconnectors 18a and exposed nuts and bolts 19a joining purlins 16a torafters 17a. Condensate formed on glazing panels 12a is collected incondensate channels 21a formed by a wide bottom flange 23a projectinglaterally from and on opposite sides of a central upstanding web 25a.Condensate is also collected in similar rafter condensate channels 27aformed by a wide bottom flange 29a projecting laterally from and onopposite sides of a central upstanding web 3la on the rafters 16a. Theseprior art rafters 16a and purlins 17a have upper transverse flanges 33aand 35a, respectively, projecting laterally from their respectivecentral webs resulting in an I beam cross-sectional appearance for therafters 17a and purlins 16a.

In these prior art frameworks 14a, the bottom flanges 23a of the purlinsare disposed above the bottom flanges 29a of the rafters; with ends 37athereof spaced from rafters 31a to allow condensate to flow over theflange ends 37a and to drop into the underlying rafter condensatechannels 27a. Additionally, any moisture leaking past, i.e., by-passing,glazing seals 38a or fasteners 39a for fastening glazing bars or caps40a to the purlins 16a is collected in internal bypass channels 41a atthe top of the purlins 16a and carried to the ends of the purlins andallowed to flow down along the rafters central web 31a into the raftercondensate channel 27a. In a similar manner, moisture by-passing rafterglazing seals 42a or bypassing fasteners for its glazing bar or cap 43awas collected in internal bypass channels 44a on the rafters 17a. Whereconsiderable bypass moisture was present, it could flow down along therafter web 31 a and cause a back flow of moisture into a purlincondensate channel 21a. Thus, the bypass moisture and condensatemoisture were collected at different levels in the purlins and thendeposited in the rafter condensate channels 27a.

Also, in the prior art frameworks 14a, exposed right angle connectors18a and bolts 19a are used to fasten the intersecting purlins 16a to therafters 17a. These connectors, bolts, and nuts, as well as the spacedtop flanges 33a, 35a and bottom flanges 23a, 29a, contribute to anoverall cluttered appearance to the structure which is desired to beovercome. Also, while the bypass and the condensate moisture aregenerally collected, the condensate channels are objectionable to somepeople and for certain applications as being too wide and too exposed toview.

In accordance with the present invention, the skylight structure 11 isformed with a clean, neat and uncluttered appearance with closedtubular-shaped pur lins l6 and rafters 17 (FIG. 4) having hollowinteriors with small condensate channels 21 and 27 being formed in theupper portions of the purlins l6 and rafters 17 adjacent the glazingpanels 12. More specifically, the purlins and rafters 16 and 17 derivesufficient rigidity and strength from their tubular bodies 45 and 46,usually formed of extruded aluminum, and have thereon hidden condensatechannels 21 and 27, as will be explained in greater detail. Also, thepurlins 16 are preferablyinterconnected to the rafters 17 by a hidden,i.e., non-exposed interconnection, rather than by the exposed bolts 19aand connectors 18a used with prior structure shown in FIGS. 2 and 3.

Preferably, the condensate channels 21 in the purlins 16 are disposedadjacent to and extend longitudinally of the purlins with a pair ofglazing supports 47 also carried along the upper portions of the purlins16 upon which rest first marginal edges of a pair of adjacent glazingpanels 12. The purlin condensate channels 21 and bypass channels 94 areat substantially the same level. Similarly, a pair of glazing supports48 are disposed adjacent to and extend longitudinally of the rafter17with bypass channels 94 and 94a adjacent the level of the raftercondensate channels 27. Preferably, outer sides of the purlin condensatechannels 21 are formed as extensions of and coplanar with vertical, sidewalls 49 of the tubular body and extend to upper edges 51 positionedrelatively close to the glazing panels 12. In a like manner, the outersides of the rafter condensate channels 27 are formed as extensions ofand coplanar with vertical side walls 50 of the rafter and extend toupper edges 52 adjacent the glazing panels 12. Thus, the presence of thecondensate channels will not be readily, if at all, noticeable frombelow.

Also, to enhance the appearance, as viewed from beneath, the purlins 16and rafters 17 are preferably interconnected by hidden interconnectormeans 53, as best seen in H6. 6. The preferred interconnector means 53between the purlins 16 and rafters 17 further comprises forming a curbor projection 54 on an end 55 of a purlin 16 to seat in a notch 57formed in outer rafter condensate channel walls 58. In this instance,ends 59 of the purlin side walls 49 abut the vertical side walls 50 ofthe rafters 17. To prevent separation of the purlin curbs 54 from therafter while still allowing clearance and tolerances for construction,the interconnecting means 53 further comprises retaining pin means 61comprising pins 63 and 65. The pins 63 are secured in apertures in thepurlins l6 and project downwardly into the rafter condensate channels 27to abut the outer condensate channel walls 58 if the purlins 16 shouldtend to separate from the rafters 17. Longitudinally extending pins 65may be inserted into holes or spaces formed in the purlins and rafterstoextend therebetween to hold the purlins against shifting or liftingrelative to the rafters. Thus, the hidden notching and hidden pinsinterconnect the purlins 16 and rafters against separation and largeshifting movements relative to one another.

Referring now in greater detail to the individual elements of theskylight structure 11, the illustrated purlins l6 and rafters 17 arepreferably formed of lightweight metal extrusions, for example ofaluminum, with the closed tubular bodies enclosing a hollow interiorspace 73. in addition to the vertical side walls 49 and 50, the purlins16 and rafters 17 each have a bottom wall spanning a pair of side wallsand joined thereto at integral corners 77. Also, each purlin l6 andrafter 17 has a top wall 79 which is disposed substantially parallel tothe bottom wall 77 and which also is joined to the upper ends of thevertical side walls at right angled integral corners. in this instance,the purlin has a generally rectangular cross-sectional shape with thetop and bottom walls 75 and 79 being longer than the vertical side walls49.

Referring now in greater detail to the purlin 16, the condensatechannels 21 each are defined by an open top, an outer vertical side atcondensate wall 58, a bottom side 81 and an inner vertical side at avertical wall 83. In this instance, the condensate channels are formedwith a generally rectangular cross section. The inner channel wall 83 isspaced from ends 37 of the purlins 16 supported on the rafter and isparallel to the outer channel wall 58 and extends upwardly slightlyabove the upper edge 51 of the condensate outer wall 58 to terminate ata horizontal surface 85 of an extruded body 86 for the glazing support47.

The marginal edges 15 of the glazing panels 12 are spaced slightly abovethe open tops of the purlin condensate channels 21 and inwardly thereofto'purlinsupporting, glazing strips 87. The latter each have a lowerspline shaped section 89 inserted into a complementary cross sectionslot 91 in the extruded body 86 and rest on the top surface 85 thereof.The upper edges of the glazing strip 87 are formed with sawtooth edgeswhich are flattened slightly by the pressure from the exterior clampingor glazing bar 40 to provide a weathertight seal against the passage ofmoisture between the glazing panel 12 and the glazing strip 87. Thepreferred glazing strips 87 are formed of neoprene to provide resilientsupport surfaces which will provide a weathertight seal with the glazingpanels. The purlin glazing strips 87 space interior sides 93 of theglazing panels 12 slightly above upper edges 51 of the condensatechannels 21 so that condensate may flow along the glazing panels to thevertical sides of the glazing strips 87 and then flow down along theinner channel wall 83 and into the condensate channels 21 for deliveryto the rafter condensate channels.

The marginal portions 15 of the glazing panels 12 have vertical edges 92which are abutted against and cushioned by a glazing block 93 made of asuitable re-' silient material such as neoprene carried in a groove 94on the top portion of the purlin 16. More specifically, the glazingblock 93 is generally rectangular in cross section and extendslongitudinally the length of the purlin and extends vertically above theglazing strip 87 and between the edge 92 of the glazing panel and one ofa pair of upstanding cap-securing walls 95 and 96. While the purlin 16shown in FIGS. 4 and 5 has only one glazing block 93 on the uphill sideof the purlin, a second glazing block 93 may be inserted into the otherempty groove 94.

The grooves 94 function to collect and to convey external water whichhas leaked into the skylight. A center groove or channel 94 functions tocollect and to convey external water which may have leaked past fastener39. The grooves 94 and 94a thus serve as a bypass means to collect andtransfer by-pass water.

Th glazing cap 40 is located relative to the purlin 16 and is secured toa pair of upstanding, cap-securing walls 95 and 96 which extendlongitudinally of the purlin with upper edges thereof extending abovethe glazing panels 12 to project between a pair of longitudinallyextending, depending flanges 97 formed on the inwardly facing side ofthe glazing cap. More specifically, lower marginal portions of the capflanges 97 abut the outer sides of the cap-securing walls 95 and 96 andcenter the cap relative to the purlin 16 and edges of the glazing panels12. The width of the space between the cap securing flanges 95 and 96 isless (at least at the lower portion of the space) than the outsidediameter of the threads on cap screw shanks 99 to allow the selftappingscrews 39 to screw into the cap-securing walls 95 and 96. Suitableopenings are formed in the glazing caps 40 to allow the screw shank toproject down and to screw into the walls 95 and 96 as the cap screw isturned. The preferred glazing cap 40 is formed of extruded aluminum andcovers the area between adjacent glazing panels 12.

On the underside of the glazing caps 40 are a pair of resilient glazingseals 101 which are compressed against the exterior side of the glazingpahels 12 to provide a weatherproof seal along the exterior of theglazing panels. The glazing strips 101 in glazing are similar to andopposite to the glazing strips 87 carried by the purlins l6 and hencewill not be described in greater detail.

Turning now in greater detail to the rafter 17, it has a glazing cap 43generally similar to the glazing cap 40 in that it has a pair ofdepending longitudinally extending flanges 97 for abutting against theupper marginal edges of a pair of similar upstanding cap locating andsecuring walls 95'and 96. The glazing cap 43 for the rafter also has apair of glazing strips 101 for sealing against the other exteriormargins of the glazing panels 12 and holding them against the underneathpair of glazing strips 87 carried by the rafter 17 in glazing stripbodies 86. As in the purlins, glazing blocks 93 are carried in thegrooves 94 at the top wall of the rafter 17 to abut edges 92 of theglazing panels 12. As the glazing strips 87, glazing blocks 93, andcooperation of the flanges 95 and 96 with the glazing cap 43 aresubstantially the same in structure and function for both the rafters 17and the purlins 16, they will not be described in any greater detail. I

The condensate channels 27 for the rafter 17 are formed with open topsand extend downwardly to a greater depth than the purlin condensatechannels 21 the bottom condensate walls are beneath and spaced below theglazing strip bodies 86 to project into the hollow interior 73 of therafter. From the inward edge of the bottom walls 105, a wall 107 extendsupwardly to and is integrally joined to the underside of the glazingstrip body 86 and forms therewith a horizontally directed shoulder 109which interconnects this lower wall 107 and upstanding outwardly facingwall 83 of the glazing strip body 86. Thus, as readily seen in HQ. 7,the condensate channels 27 in the rafters 17 have their bottom wallsspaced beneath the bottom sides 81 of the condensate channels 21 so thatliquid will flow through the discharge openings 37 therein into therafter condensate channels 27.

As best seen in FIG. 6, the horizontally extending purlins 16 aresupported by the vertically extending rafters l7 and interconnectedthereto at spaced locations along the length of the rafters at notches57which receive the curbs 54 at the ends 55 of the purlins. Theinterconnecting means 53 secures the purlins against shifting from orseparation from the rafters. The illustrated notches 57 are formed inthe upper portion of the outer condensate channel walls 58 by makingdownward saw cuts to form cuts 111 spaced from each other by a distanceslightly greater than the width of the purlin. The portion of the outercondensate wall 58 between the cuts 111 is removed as by being eitherbent and snapped off or cut from the rafter to form a horizontallyextending support 114. The respective notches 57 extend downwardly to apredetermined depth and are related to the vertical dimension of thecurb 54 with the result that when the curb lower wall 113 is placed onsupport 114 the glazing strips 87 on the purlins and rafters are alignedin a common plane to support the glazing panels 12. The curbs 54 on thepurlins project outwardly from the vertical extending wall ends 71,which are abutted against the outer side walls 50 of the rafter tubularbodies, so that leading end walls 115 of the curbs 54 either engage oralmost engage the outwardly facing walls 83 of the glazing strip bodies86 on the rafter 17. Thus, the opposed purlins 16 are limited inrelative movement inwardly toward each other and are limited againstturning relative to the rafter by the walls at cuts 111 of the notches57. The outward movement of the purlins 16 relative to one another andtwisting of the purlins relative to the rafters 17 is prevented by theinterconnecting means 53 which includes the horizontally extending pins65 and the pins 63 which project downwardly from the purlins into thecondensate channels 27. Preferably, the pins 63 and 65 are cylindrical,roll pins. Two pins 63 are forced into cylindrical bores drilled intothe bottom of the glazing strip bodies 86 beneath the glazing strips 87.The pins 63 project downwardly of the wall 114 at the notches 57 to aposition spaced above the bottom wall 105a of the rafter condensatechannel. Should the purlins l6 tend to separate from the rafters 17, theroll pins 63 will abut the walls 58 and resist any such separatingmovement.

The purlins 16 are held by the notches 57 against shiftinglongitudinally of the rafter 17 and additionally are further held andaligned more precisely with other purlins 16 by the pins 65. Morespecifically, the pins 65, as best seen in FIG. 6, have one end forcedinto openings 121 in the glazing strip bodies 56 of the rafters 17 withopposite ends projecting horizontally to be received into the spacebetween the upstanding capsecuring walls 95 and 96 as best seen in FIGS.and 7. Also, the purlins 16 are held against lifting by the rafterglazing cap 43 which extends over the curbs 54 on the purlins. Thepurlin glazing caps extend between and terminate at the glazing caps 43for adjacent rafters 17.

In accordance with the further embodiments of the invention illustratedin FIGS. 8-11,;a'double glazing skylight construction is provided withthe im--' rior glazing panels separated by a large air. space 147therebetween. As will be explained in greater detail, only the exteriorglazing panels 143 receive large amounts-of condensate or bypassmoisture. As'with the single glazed structure purlin l6 of FIGS. 4-7,the purlin's 140 have condensate channels 151 formed in the top portionsthereof and adjacent the exterior glazing panels 143 to collectcondensate andto deliver the collected condensate. to rafter Condensatechannels 153 formed in the upper portions of the rafters 1:41 adjacentthe upper glazing panels 143. In this instance, only a single purlincondensate channel 151 is provided for collecting condensate along thedownward sloping side of the glazing panels 143. An'end 155 of thecondensate channel is spaced from a wall 156 of the rafter, as best seenin FIG. 9, to allow moisture discharging from a bottom'wall 157 of thechanel to drop through the space between its end 157 and rafter wall156.and collect in the underlying rafter condensate channels 153.

. The upper glazing panels v143 rest upon and are supported byresilient, neoprene glazing strips 161yon the respective purlins 140and. rafters 141, the glazing strips 161 being substantially'identicalto the glazing strips 87 hereinbefore described. On the exterior side ofthe upper glazing panels 143' is a purlin glazing cap 163 which issubstantially identical to the purlin glazing cap 40'and hence will notbe described in detail herein. Likewise,the rafter glazing caps 165 forexterior glazing panels 143 are substantially similar in constructionand function to the rafter glazing cap 43 hereinbefore described andwill not be described again. Also, glazing blocks 169 are disposedagainst the edges of the exterior glazing panels 143 and are supportedin the manner of the glazing blocks 93. The glazing blocks 169 arecarried in grooves 170 which also serve to collect exterior waterby-passing the glazing cap40. A central groove 170a to receive the screwfastener for the rafter glazing cap 165 also serves as a by-pass watercollecting channel.

The purlin condensate channels 151 are disposed slightly beneath theinterior sides of the upper glazing panels 143 and along the top of thepurlins 140. In this instance, the purlin condensate channels 151 areformed as an extension of an upper transverse wall or flange whichextends generally horizontally and upper side of the lower carries theglazing strips 161 and the glazing block 169. More specifically, abottom wall 176 for the condensate channel is in a common plane with andintegrally joined to the flange 175. This bottom wall 176 extends to anupwardly inclined outer condensate wall 177 which is spaced from aninner condensate channel wall 179 formed on the glazing strip body. Ifdesired, a second condensate channel 151 may be formed on the other sideof the purlin 140.

The rafter condensate channels 153 in the rafters 141 are disposed at aslightly lower level than the purlin condensate channels 151 and have a,greater depth and width than the condensate channels 151. The raftercondensate channels are formed at the top portionsof the raftersadjacent the interior side .of the upper glazing panels; and are formedwith an open top, an outer vertical wall 181, a bottom wall 183, and aninner wall extending to the underside of .the glazing strip body,

A top edge 188 for the outer condensate walls 181. is

preferably-located at a position beneath the transverse flange 175 onthe purlin to. assure that the purlin and rafter glazing strips 161 arealigned in a common'plane for supporting the upper glazing panels 143when ends of the purlin flanges 175 reston the upper edge'l88 of rafter.The purlin 141 has a central vertically extending web l9l'which extendsfrom the top flange 175 to a lower transversely extendingflange 193which carries a pair of glazing supports 195 each having apair ofglazing strips 197 for supporting the marginal edges of the lowerglazing panels 145. Glazing blocks 199 abut the edges of the glazingpanels 145 and are disposed in grooves 201 between the glazing stripbodies 195 and one of apair of upstanding, longitudinally extendingwalls 203 spaced from and on opposite, sides of the central web 191.

' A pair of inner glazing caps 205 of Z-shaped configuration are securedto opposite sides of the central web 191' of the purlin to hold thelower glazing panels 145 in position against the glazing strips 197.More particularly, the inner glazing caps 205 have an upstandingsecuring flange 209 which is apertured to receive bolt and nut fasteners211 to fasten the caps 205 tightly against the central web 191. Theinner glazing caps are formed with an outward transversely extendingplate 213 integral with the securing flange 209 which at its outer endis formed with a depending glazing strip body 215 carrying a lowerglazing strip 217 abutting the glazing panel 145 at a position oppositethe purlin glazing strips 197. In this manner, the lower glazing panels145 are secured to the purlins and rafters. As best seen in FIG. 8, itis preferred to provide a clean bottom appearance formed by having thebottom surfaces of the purlins and rafters intersect, abut, and be flushwith each other.

The purlins 140 and rafters 141 are interconnected by a angle-shapedconnectors 221 which have one leg 223 fastened by a nut and boltconnection 225 to the central web 191 of the rafter. A second leg 227 ofthe connector 221 is fastened in a similar manner by a nut and boltfastener 229 to a web 191 of the purlin 140.

In the preferred manner of interconnection, the rafters 141 are uncutwith the ends of the purlins cut as best seen in H6. 9 to provide a topcurb 230 and a lower web projection 231. The latter projects from thecurb 230 into the space between the upper and lower flanges 175 and 193on the rafter 141. A hole 237 is drilled into the projection to receivethe shank of the bolt of the fastener 229. Preferably the projection 231extends to a leading end 237 which may abut or be closely adjacent tothe rafter central web 191. The projection has an upper side 239 whichextends beneath the end 233 of the upper transverse flange 175 for thepurlin to form the curb 230 to allow it to project over the raftercondensate channel 153 and to rest on the edge 188 of its outercondensate wall 181, as illustrated in FIGS. 8-11. Thus, the bottom wall157 the purlin condensate channel 151 may be superposed over the raftercondensate channel and condensate may discharge through the opening 155into the underlying channel 153.

From the foregoing it will be seen that the purlins and rafters may beformed with condensate channels along their upper portions adjacent theglazing panels and that the prior art wide lower condensate flanges andchannels may be eliminated. With the present invention, the condensatechannels may be completely hidden, as viewed from below, or at leastmade inconspicuous. Also, the interconnecting means between channels mayalso be hidden or obscured from direct view therely eliminating thecluttered appearance of prior art interconnections. The overall skylightconstruction, the purlins and rafters are formed of simple andeconomical extrusions which are cooperatively related in a novel mannerto provide a strong safe structure at low cost and yet a skylightstructure which will more adequately collect and remove moisture.

While a preferred embodiment has been shown and described, it will beunderstood that there is no intent to limit the invention by suchdisclosure but, rather, it is intended to cover all modifications andalternate constructions falling within the spirit and scope of theinvention as defined in the appended claims.

What is claimed is:

1. In a skylight structure having a set of glazing panels and aframework supporting said panels, the improvement comprising purlins insaid framework extending between a pair of adjacent rafters, saidpurlins having an elongated structural body, a pair of glazing supportson the upper portions of said purlin bodies extending longitudinally tosupport first edges of adjacent pairs of said glazing panels, meansintegral with said purlin bodies defining a pair of purlin condensatechannels each extending longitudinally along said upper portion of saidpurlin body and adjacent to said glazing panels for receiving andcarrying condensate, elongated rafters spaced from each other andsupporting said purlins and having a structural body, a pair of glazingsupports on said rafters on the upper portion of said body extendinglongitudinally of said rafters for supporting the other edges of theglazing panels, means integral with rafter structure body defining apair of condensate channels extending longitudinally along the upperside of said rafter structural body for receiving condensate from saidglazingpanels, said purlin condensate chan nels having portions disposedabove and discharging moisture downwardly into underlying raftercondensate channels and interconnecting means securing said purlins andrafters to each other each of said purlin and rafter comprising a closedtubular body having a hollow interior, each of said tubular bodiescomprising a pair of vertically extending side walls, a bottom walljoined to lower ends of said vertical side walls, and a top wall joinedto the upper ends of said vertical side walls, said glazing supportsbeing disposed along said top wall of said purlin and inwardly andintermediate of said condensate channels and projecting upwardly of theupper edges of said purlin vertical side walls to space said glazingpanels therefrom, means disposed centrally of said purlins and betweensaid glazing supports on said top wall to secure a cap means thereto,said rafter glazing supports being disposed along said top wall of saidrafter and inwardly and intermediate said rafter condensate channels andprojecting upwardly of the upper edges of said rafter vertical sidewalls to space said glazing panels therefrom, said glazing panels beingspaced upwardly of said condensate channels in said purlins and saidrafters and extending thereacross and means disposed centrally alongsaid rafters and between said glazing supports on said top wall tosecure a cap means thereto.

2. In a skylight structure having a set of glazing panels and aframework supporting said panels, the improvement comprising purlins insaid framework extending between a pair of adjacent rafters and havingan elongated substantially closed tubular structural body, spacedglazing supports on said purlins extending along an upper longitudinallyextending side of said tubular body to support first edges of a pair ofsaid glazing panels, means integral with said closed tubular bodydefining a pair of condensate channels each extending longitudinallyalong an upper portion of said body and adfa-- cent said glazing panelsfor receiving and carrying condensate therefrom, elongated raftersspaced from each other and supporting said purlins and havingsubstantially closed structural bodies, glazing supports on said raftersextending longitudinally of said rafters along an upper longitudinallyextending side of said closed body for supporting the other edges ofsaid glazing panels, means integral with said closed tubular rafter bodydefining a pair of spaced condensate channels extending longitudinallyalong an upper longitudinally extending portion of said closed rafterbody for receiving condensate from said glazing panels and from saidcondensate channels of said purlins joined to opposite sides of saidrafters, cap means on the exterior side of said glazing panels forfastening to said purlins and rafters to hold said glazing panels onsaid glazing supports; and interconnecting means securing said purlinsto said rafters to provide said framework each of said purlin and raftercomprising a closed tubular body having a hollow interior, each of saidtubular bodies comprising a pair of vertically extending side walls, abottom wall joined to lower ends of said vertical side walls, and a topwall joined to the upper ends of said vertical side walls, said glazingsupports being disposed along said top wall of vraid purlin and inwardlyand intermediate of said con densate channels and projecting upwardly ofthe upper edges of said purlin vertical side walls to space said glazingpanels therefrom, means disposed centrally of said purlins and betweensaid glazing supports on said top wall to secure a cap means thereto,said rafter glazing supports being disposed along said top wall of saidrafter and inwardlyand intermediate said rafter condensate channels andprojecting upwardly of the upper edges of said rafter vertical sidewalls to space said glazing panels therefrom, said glazing panels beingspaced upwardly of said condensate channels in said purlins and saidrafters and extending thereacross and means disposed centrally alongsaid rafters and between said glazing supports on said top wall tosecure a cap means thereto.

3. A skylight structure in accordance with claim 2 in which said glazingsupports comprise means defining a pair of longitudinally extendingchannels along said top wall and flexible resilient glazing stripstherein for supporting the marginal edges of said glazing panels, saidcondensate channels being closely adjacent and parallel to said glazingstrips.

4. A skylight structure in accordance with claim 2 in which the upperlongitudinally extending edges of said side walls of said rafters arenotched and in which said top walls of said purlins are formed withlongitudinally extending projections inserted into said notches to besupported by said underlying rafters.

5. In a skylight structure having a set of glazing panels and aframework supporting said panels, the improvement comprising purlins insaid framework extending between a pair of adjacent rafters and havingan elongated substantially closed tubular structural body, spacedglazing supports on said purlins extending along an upper longitudinallyextending side of said tubular body to support first edges of a pair ofsaid glazing panels, means integral with said closed tubular bodydefining a condensate channel extending longitudinally along an upperportion of said body and adjacent said glazing panels for receiving andcarrying condensate therefrom, elongated rafters spaced from each otherand supporting said purlins and having substantially closed structuralbodies, glazing supports on said rafters extending longitudinally ofsaid rafters along an upper longitudinally extending side of said closedbody for supporting the other edges of said glazing panels, meansintegral with said closed tubular rafter body defining a pair of spacedcondensate channels extending longitudinally along an upperlongitudinally extending portion of said closed rafter body forreceiving condensate from said glazing panels and from said condensatechannels of said purlins joined to opposite sides of said rafters, capmeans on the exterior side of said glazing panels for fastening to saidpurlins and rafters to hold said glazing panels on said glazingsupports; and interconnecting means securing said purlins to saidraftersto provide said framework, said interconnecting means comprisinglocating and retaining pins extending between said purlins and raftersto hold against the separation of one from the other, and certain ofsaid locating pins being secured in said purlins and project downwardlytherefrom into said condensate channels in said rafters.

6. A structure in accordance with claim 5 in which other locating pinsextend in a direction parallel to the longitudinal direction of saidpurlins and project between said purlins and rafters.

1. In a skylight structure having a set of glazinG panels and aframework supporting said panels, the improvement comprising purlins insaid framework extending between a pair of adjacent rafters, saidpurlins having an elongated structural body, a pair of glazing supportson the upper portions of said purlin bodies extending longitudinally tosupport first edges of adjacent pairs of said glazing panels, meansintegral with said purlin bodies defining a pair of purlin condensatechannels each extending longitudinally along said upper portion of saidpurlin body and adjacent to said glazing panels for receiving andcarrying condensate, elongated rafters spaced from each other andsupporting said purlins and having a structural body, a pair of glazingsupports on said rafters on the upper portion of said body extendinglongitudinally of said rafters for supporting the other edges of theglazing panels, means integral with said rafter structure body defininga pair of condensate channels extending longitudinally along the upperside of said rafter structural body for receiving condensate from saidglazing panels, said purlin condensate channels having portions disposedabove and discharging moisture downwardly into underlying raftercondensate channels and interconnecting means securing said purlins andrafters to each other each of said purlin and rafter comprising a closedtubular body having a hollow interior, each of said tubular bodiescomprising a pair of vertically extending side walls, a bottom walljoined to lower ends of said vertical side walls, and a top wall joinedto the upper ends of said vertical side walls, said glazing supportsbeing disposed along said top wall of said purlin and inwardly andintermediate of said condensate channels and projecting upwardly of theupper edges of said purlin vertical side walls to space said glazingpanels therefrom, means disposed centrally of said purlins and betweensaid glazing supports on said top wall to secure a cap means thereto,said rafter glazing supports being disposed along said top wall of saidrafter and inwardly and intermediate said rafter condensate channels andprojecting upwardly of the upper edges of said rafter vertical sidewalls to space said glazing panels therefrom, said glazing panels beingspaced upwardly of said condensate channels in said purlins and saidrafters and extending thereacross and means disposed centrally alongsaid rafters and between said glazing supports on said top wall tosecure a cap means thereto.
 2. In a skylight structure having a set ofglazing panels and a framework supporting said panels, the improvementcomprising purlins in said framework extending between a pair ofadjacent rafters and having an elongated substantially closed tubularstructural body, spaced glazing supports on said purlins extending alongan upper longitudinally extending side of said tubular body to supportfirst edges of a pair of said glazing panels, means integral with saidclosed tubular body defining a pair of condensate channels eachextending longitudinally along an upper porioon of said body andadjacent said glazing panels for receiving and carrying condensatetherefrom, elongated rafters spaced from each other and supporting saidpurlins and having substantially closed structural bodies, glazingsupports on said rafters extending longitudinally of said rafters alongan upper longitudinally extending side of said closed body forsupporting the other edges of said glazing panels, means integral withsaid closed tubular rafter body defining a pair of spaced condensatechannels extending longitudinally along an upper longitudinallyextending portion of said closed rafter body for receiving condensatefrom said glazing panels and from said condensate channels of saidpurlins joined to opposite sides of said rafters, cap means on theexterior side of said glazing panels for fastening to said purlins andrafters to hold said glazing panels on said glazing supports; andinterconnecting means securing said purlins to said rafters to providesaid frAmework each of said purlin and rafter comprising a closedtubular body having a hollow interior, each of said tubular bodiescomprising a pair of vertically extending side walls, a bottom walljoined to lower ends of said vertical side walls, and a top wall joinedto the upper ends of said vertical side walls, said glazing supportsbeing disposed along said top wall of said purlin and inwardly andintermediate of said condensate channels and projecting upwardly of theupper edges of said purlin vertical side walls to space said glazingpanels therefrom, means disposed centrally of said purlins and betweensaid glazing supports on said top wall to secure a cap means thereto,said rafter glazing supports being disposed along said top wall of saidrafter and inwardly and intermediate said rafter condensate channels andprojecting upwardly of the upper edges of said rafter vertical sidewalls to space said glazing panels therefrom, said glazing panels beingspaced upwardly of said condensate channels in said purlins and saidrafters and extending thereacross and means disposed centrally alongsaid rafters and between said glazing supports on said top wall tosecure a cap means thereto.
 3. A skylight structure in accordance withclaim 2 in which said glazing supports comprise means defining a pair oflongitudinally extending channels along said top wall and flexibleresilient glazing strips therein for supporting the marginal edges ofsaid glazing panels, said condensate channels being closely adjacent andparallel to said glazing strips.
 4. A skylight structure in accordancewith claim 2 in which the upper longitudinally extending edges of saidside walls of said rafters are notched and in which said top walls ofsaid purlins are formed with longitudinally extending projectionsinserted into said notches to be supported by said underlying rafters.5. In a skylight structure having a set of glazing panels and aframework supporting said panels, the improvement comprising purlins insaid framework extending between a pair of adjacent rafters and havingan elongated substantially closed tubular structural body, spacedglazing supports on said purlins extending along an upper longitudinallyextending side of said tubular body to support first edges of a pair ofsaid glazing panels, means integral with said closed tubular bodydefining a condensate channel extending longitudinally along an upperportion of said body and adjacent said glazing panels for receiving andcarrying condensate therefrom, elongated rafters spaced from each otherand supporting said purlins and having substantially closed structuralbodies, glazing supports on said rafters extending longitudinally ofsaid rafters along an upper longitudinally extending side of said closedbody for supporting the other edges of said glazing panels, meansintegral with said closed tubular rafter body defining a pair of spacedcondensate channels extending longitudinally along an upperlongitudinally extending portion of said closed rafter body forreceiving condensate from said glazing panels and from said condensatechannels of said purlins joined to opposite sides of said rafters, capmeans on the exterior side of said glazing panels for fastening to saidpurlins and rafters to hold said glazing panels on said glazingsupports; and interconnecting means securing said purlins to saidrafters to provide said framework, said interconnecting means comprisinglocating and retaining pins extending between said purlins and raftersto hold against the separation of one from the other, and certain ofsaid locating pins being secured in said purlins and project downwardlytherefrom into said condensate channels in said rafters.
 6. A structurein accordance with claim 5 in which other locating pins extend in adirection parallel to the longitudinal direction of said purlins andproject between said purlins and rafters.